Kansas City Public Schools says it has decided to release students early from all district schools for the rest of the week as temperatures soar across the city. The area is expecting heat index temperatures of over 110 degrees.

Many of the secondary buildings in the district’s schools do not have central air conditioning, which is raising fears of students being subjected to possible heat-related health issues. Many school buses also do not have air conditioning.

The schools are releasing on a staggered schedule, with eight ending their school day at 10:50 a.m., another 13 will release at 11:50 a.m. and the final 11 (mostly elementary schools) will end their day at 12:45 p.m.

“The National Weather Service has issued an Excessive Heat Warning for our area, and the heat index is expected to soar well over 100 degrees each day this week,” the school’s website reads. “In light of this intense heat wave, we have made the decision to release students early from all of our schools for the rest of the week.”

The move has upset some parents, due to the need to find childcare or adjust their working hours with little notice, which could be problematic for some guardians.

That’s the same worry parents in roughly 850 school districts are facing in cities and municipalities that have shifted from a five-day school week to a four-day one this year. Officials in those districts say the move in meant to incentivize teachers to remain on the job and recruit new ones.

Kansas City is just the latest city to adjust its usual procedures due to this summer’s intense heat wave. In Arizona, many outdoor workers have shifted their hours as a heat dome (another term for a ridge of high pressure) kept temperatures above 110 degrees for over a month.